Bug 655682 - Perform discretionary flushes in the HTML parser even if the current node is foster-parenting. r=bzbarsky.

parser/html/nsHtml5StreamParser.cpp

@@ -1159,13 +1159,11 @@ nsHtml5StreamParser::ContinueAfterScripts(nsHtml5Tokenizer* aTokenizer,
       mSpeculations.RemoveElementAt(0);
       if (mSpeculations.IsEmpty()) {
         // yes, it was still the only speculation. Now stop speculating
-        if (mTreeBuilder->IsDiscretionaryFlushSafe()) {
-          // However, before telling the executor to read from stage, flush
-          // any pending ops straight to the executor, because otherwise
-          // they remain unflushed until we get more data from the network.
-          mTreeBuilder->SetOpSink(mExecutor);
-          mTreeBuilder->Flush();
-        }
+        // However, before telling the executor to read from stage, flush
+        // any pending ops straight to the executor, because otherwise
+        // they remain unflushed until we get more data from the network.
+        mTreeBuilder->SetOpSink(mExecutor);
+        mTreeBuilder->Flush(PR_TRUE);
         mTreeBuilder->SetOpSink(mExecutor->GetStage());
         mExecutor->StartReadingFromStage();
         mSpeculating = PR_FALSE;
@@ -1268,15 +1266,9 @@ nsHtml5StreamParser::TimerFlush()
 
   // we aren't speculating and we don't know when new data is
   // going to arrive. Send data to the main thread.
-  // However, don't do if the current element on the stack is a 
-  // foster-parenting element and there's pending text, because flushing in 
-  // that case would make the tree shape dependent on where the flush points 
-  // fall.
-  if (mTreeBuilder->IsDiscretionaryFlushSafe()) {
-    if (mTreeBuilder->Flush()) {
-      if (NS_FAILED(NS_DispatchToMainThread(mExecutorFlusher))) {
-        NS_WARNING("failed to dispatch executor flush event");
-      }
+  if (mTreeBuilder->Flush(PR_TRUE)) {
+    if (NS_FAILED(NS_DispatchToMainThread(mExecutorFlusher))) {
+      NS_WARNING("failed to dispatch executor flush event");
     }
   }
 }

parser/html/nsHtml5TreeBuilderCppSupplement.h

@@ -602,9 +602,18 @@ nsHtml5TreeBuilder::HasScript()
 }
 
 PRBool
-nsHtml5TreeBuilder::Flush()
+nsHtml5TreeBuilder::Flush(PRBool aDiscretionary)
 {
-  flushCharacters();
+  if (!aDiscretionary ||
+      !(charBufferLen &&
+        currentPtr >= 0 &&
+        stack[currentPtr]->isFosterParenting())) {
+    // Don't flush text on discretionary flushes if the current element on
+    // the stack is a foster-parenting element and there's pending text,
+    // because flushing in that case would make the tree shape dependent on
+    // where the flush points fall.
+    flushCharacters();
+  }
   FlushLoads();
   if (mOpSink) {
     PRBool hasOps = !mOpQueue.IsEmpty();
@@ -667,14 +676,6 @@ nsHtml5TreeBuilder::AddSnapshotToScript(nsAHtml5TreeBuilderState* aSnapshot, PRI
   mOpQueue.ElementAt(mOpQueue.Length() - 1).SetSnapshot(aSnapshot, aLine);
 }
 
-PRBool 
-nsHtml5TreeBuilder::IsDiscretionaryFlushSafe()
-{
-  return !(charBufferLen && 
-           currentPtr >= 0 && 
-           stack[currentPtr]->isFosterParenting());
-}
-
 void
 nsHtml5TreeBuilder::DropHandles()
 {

parser/html/nsHtml5TreeBuilderHSupplement.h

@@ -72,8 +72,6 @@
 
     ~nsHtml5TreeBuilder();
     
-    PRBool IsDiscretionaryFlushSafe();
-
     PRBool HasScript();
     
     void SetOpSink(nsAHtml5TreeOpSink* aOpSink) {
@@ -84,7 +82,7 @@
       mOpQueue.Clear();
     }
     
-    PRBool Flush();
+    PRBool Flush(PRBool aDiscretionary = PR_FALSE);
     
     void FlushLoads();